Solid calcium hydroxide, Ca(OH)2, is dissolved in water until the pH of the solution is 10.23.
What is the concentration of calcium ion [Ca
2+
]?
........Ca(OH)2 ==> Ca^2+ + 2OH^-
pH = 10.23
pOH = 14-10.23 = 3.77
pOH = -log(OH^-) so OH^- is approximately 1.7E-4M.
(Ca^2+) is 1/2 that
idk
To determine the concentration of calcium ion [Ca²⁺], we need to consider the dissociation of calcium hydroxide in water:
Ca(OH)₂ → Ca²⁺ + 2OH⁻
Since calcium hydroxide dissociates in water to form one Ca²⁺ ion for every Ca(OH)₂ molecule, the concentration of Ca²⁺ will be equal to the concentration of Ca(OH)₂ that was dissolved.
Given that the pH of the solution is 10.23, we know that the concentration of hydroxide ions [OH⁻] is 10^(-10.23) M.
Since Ca(OH)₂ dissociates into 2OH⁻ ions, the concentration of Ca(OH)₂ can be determined by dividing the concentration of hydroxide ions by 2:
[Ca(OH)₂] = [OH⁻] / 2
[Ca(OH)₂] = 10^(-10.23) / 2
Now, we can calculate the concentration of calcium ion [Ca²⁺] since it is equal to the concentration of Ca(OH)₂:
[Ca²⁺] = [Ca(OH)₂]
[Ca²⁺] = 10^(-10.23) / 2
Therefore, the concentration of calcium ion [Ca²⁺] is 0.0000000047 M (or 4.7 x 10^(-9) M).
To find the concentration of calcium ion [Ca2+] in the solution, we need to use the concept of ionization and dissociation of calcium hydroxide (Ca(OH)2) in water.
Calcium hydroxide (Ca(OH)2) dissociates in water to form calcium ions (Ca2+) and hydroxide ions (OH-). The balanced equation for the dissociation reaction is:
Ca(OH)2 → Ca2+ + 2OH-
From the equation, we can see that for each mole of calcium hydroxide, we get one mole of calcium ions. Therefore, the concentration of calcium ions will be equal to the concentration of calcium hydroxide.
Given that the pH of the solution is 10.23, we can use the pH scale to find the concentration of hydroxide ions [OH-]. Since the pH is greater than 7, the solution is basic, and the concentration of hydroxide ions can be determined using the equation:
pOH = 14 - pH
Let's calculate the pOH first:
pOH = 14 - 10.23 = 3.77
Now, we can use the pOH to calculate the concentration of hydroxide ions:
[OH-] = 10^(-pOH)
[OH-]= 10^(-3.77)
Next, we need to calculate the concentration of calcium ions. Since calcium hydroxide dissociates to form one mole of calcium ions for each mole of calcium hydroxide, the concentration of calcium ions will also be equal to [OH-].
Therefore, the concentration of calcium ions [Ca2+] = [OH-] = 10^(-3.77)